The proposed research is a program for an in-depth neurophysiological study of the dorsal spinocerebellar tract (DSCT) in the cat. The long term objectives of the program are to determine the role played by sensory receptors in the control of movement and posture. The DSCT is a pathway that transmits information to the cerebellum derived from sensory receptors in the muscles, joints and skin of the hind limbs. The specific aim of this proposal is to determine what information is encoded by the DSCT for transmission to the cerebellum and how the information is encoded. The experimental design incorporates random sampling of large numbers of DSCT units to determine neuron population behavior. Quantitative data analysis is based on information theory. Principal component analysis, statistical correlations and a database management system, developed specifically for the purpose, designed to allow repeated reexamination of experimental data and protocols with different working hypotheses in a systematic and ordered manner that minimizes the need for experimental animals.